This application is a 371 of PCT/IB99/00733 filed Apr. 22, 1999.
(1) Field of the Invention
The present invention relates to a 5xe2x80x2 upstream region DNA containing a promoter of a human bone morphogenetic protein (hereafter referred to as BMP-7). Further, the present invention relates to a method for exploring a low molecular weight compound positively or negatively which regulates the expression of human BMP-7 by using a mass of animal or yeast cells that are introduced with a recombinant expression vector harboring a 5xe2x80x2 upstream region DNA containing the human BMP-7 promoter integrated into a suitable reporter gene, and by using a reporter activity as an indicator.
(2) Description of the Related Art
At present, a bone morphogenetic activity has been reported for a bone morphogenetic factor, BMP, belonging to TGF (transforming growth factor) -xcex2 superfamily (Science 150, 893-897, 1965; Science 242, 1528-1534, 1988). Known species of BMP are BMP-1 to BMP-14. Among them, the members from BMP-2 to BMP-14 have been known as showing the bone morphogenetic activity. BMPs ranging from BMP-2 to BMP-14 are considered as effective to therapeutic and preventive treatment for various bone dysfunction and bone diseases, however, they exist in very small amount in nature. Therefore, an available large quantity from BMP-2 to BMP-14 used for these treatments requires production of recombinant protein. The production of the recombinant protein generally is very expensive compared with a low molecular weight compound. Furthermore, there are many restrictions as a medical drug in terms of physical properties and administration methods due to proteinic characteristics. Considering these points, a small molecular organic compound having the activity equal to that of the BMP protein, if any, should be a highly promising medical drug. The substance obtainable with the exploring method provided by the present invention has the activity to induce the expression of human BMP-7, a bone osteogenesis factor, and also has the efficacy equal to that of human BMP-7, representing very high usefulness. On the contrary, if human BMP-7 is concerned with bone and cartilage hyperplasia, inhibiting the expression may prevent osteohyperplasia. The present invention is able to detect the inhibition of the human BMP-7 expression and provides a method for exploring a substance to prevent hyperplasia. In addition, it is known that human BMP-7 has the ability to enhance the differentiation of kidney cells (Proc. Natnl. Acad. Sci., U.S.A., Vol. 93, p. 9021-9026, 1996). Thus, the experimental system provided by the present invention can be applied to a method for exploring the agent for the treatment of the kidney disorder.
For such an exploring method, an example has been so far only reported using a murine BMP-2 promoter (WO97/15308), and there is no example of using the human BMP-7 promoter. In addition, since the materials of the exploring method provided by the present invention are all derived from human sources, it can be expected that discovered substances should show the effects at clinic practically.
The present invention provides a 5xe2x80x2 upstream region DNA containing a promoter of human BMP-7. By using 5xe2x80x2 upstream region gene containing the human BMP-7 promoter and an animal cell introduced with a recombinant expression vector that has been connected to an appropriate reporter gene, the low molecular weight compounds which regulate positively or negatively the expression of human BMP-7 can be explored with reference to a reporter activity. The low molecular weight compounds and their derivatives have morphogenetic activity and inhibiting activity for bone and cartilage through the expression of human BMP-7 and are effective as preventive or therapeutic agents for cartilage and bone diseases, remedies for osteometastasis, or therapeutic and preventive agents for excess osteogenesis. Furthermore, these low molecular weight compounds and their derivatives are useful as preventive or therapeutic agents for kidney disorders.